1. Field of the Invention
This invention relates to a tape player of the so-called center capstan type in which reel stands are provided at positions putting a capstan shaft therebetween and the capstan shaft is inserted into the center hole of a cassette half and, more particularly, to a driving device of the tape player for transmitting the turning force of the capstan shaft to the reel stands.
2. Description of the Prior Art
Micro-cassette tape and the like are driven by means of a capstan shaft inserted into the center hole of a cassette half.
For reference, FIG. 4 shows in plan view the schematic configuration of a general tape player of the so-called center capstan type in which a cassette half of the foregoing type is driven as it is inserted into the tape player. The tape player is provided with one motor M whose power is transmitted via a belt 1 to a flywheel 2. The flywheel 2 has a capstan shaft 3 formed integrally therewith and this capstan shaft 3 is supported rotatably by a housing metal (bearing) 10 provided on a chassis. The flywheel 2 has also a drive gear 4 formed integrally therewith.
By the housing metal 10 a gear arm 5 is supported rotatably, which supports a pair of idle gears 6 and 7. On the chassis there is provided a pair or reel stands Ra and Rb, and the idle gears 6 and 7 are positioned in opposition to rell gears 8 and 9 provided respectively on the reel stands. These idle gears 6 and 7 and gear arm 5 are designed so as to produce a friction torque therebetween; thus, as the drive gear 4 is driven and rotated together with the flywheel 2 by the motor M, the gear arm 5 turns in the same direction as the turning direction of the drive gear 4 before the respective idle gears 6 and 7 rotate. That is, as the drive gear 4 rotates in the clockwise direction the idle gear 6 comes into gear with the reel gear 8 of the take-up side, whereas as the same rotates in the counterclockwise direction the idle gear 7 comes into gear with the reel gear 9 of the supply side.
As is apparent from the foregoing, in order to make sure that the gear arm 5 turns when the flywheel 2 and drive gear 4 are rotated, a mechanism for producing a friction torque between the respective idle gears 6 and 7 and gear arm 5 must be interposed therebetween. As such a mechanism, in the prior art, plate spring or felt is interposed between the idle gears 6 and 7 and gear arm 5, or a frictional force appearing between the material of the idle gears 6 and 7 and the gear arm 5 is utilized.
In the prior art, however, a substantially identical frictional force is made to appear with respect to the respective idle gears 6 and 7; therefore, in the play mode wherein the left-hand-side idle gear 6 comes into gear with the reel gear 8 to drive and rotate the take-up-side reel stand Ra, the frictional force of the idle gear 6 works as a drive load. This drive load increases the power consumption of the motor and gives an influence to the dynamic precision of the player, for example, wow and flutter will appear.